Some driving assisting systems regulate an accelerator pedal reaction force based on running conditions around the own vehicle. Based on driver's behavior intention detected, the systems adjust or modify the regulated accelerator pedal reaction force. In particular, this type of driving assisting systems reduces the regulated accelerator pedal reaction force upon detecting a driver's intention to change to a new lane.
Such type of driving assisting systems is satisfactory in that a reduction in the regulated accelerator pedal reaction force allows a driver to accelerate a vehicle smoothly to pass or overtake the preceding vehicle ahead. However, this type of systems does not consider that a driver may have the same intention under various running conditions in which a vehicle is traveling. Accordingly, a need remains for varying adjustment of the accelerator pedal reaction force with different running conditions upon detecting the same driver's intention.